<div class="doc-item" id="doc-627"><h2 class="doc-item-name">binding<span class="namespace">(clojure.core)</span></h2><p class="macro">Macro</p><ul class="var-arglists"><li>(<span class="var-name">binding</span> bindings &amp; body)</li></ul><div class="var-docstring"><p>binding =&gt; var-symbol init-expr</p><p>Creates new bindings for the (already-existing) vars, with the
  supplied initial values, executes the exprs in an implicit do, then
  re-establishes the bindings that existed before.</p></div><div class="var-source"><pre>; clojure/core.clj:1118
(defmacro binding
  [bindings &amp; body]
    (assert-args binding
      (vector? bindings) &quot;a vector for its binding&quot;
      (even? (count bindings)) &quot;an even number of forms in binding vector&quot;)
    (let [var-ize (fn [var-vals]
                    (loop [ret [] vvs (seq var-vals)]
                      (if vvs
                        (recur  (conj (conj ret `(var ~(first vvs))) (second vvs))
                                (next (next vvs)))
                        (seq ret))))]
      `(do
         (. clojure.lang.Var (pushThreadBindings (hash-map ~@(var-ize bindings))))
         (try
          ~@body
          (finally
           (. clojure.lang.Var (popThreadBindings)))))))</pre></div><div class="license"><p>Copyright (c) Rich Hickey. All rights reserved.</p><p>The use and distribution terms for this software are covered by the <a href="http://opensource.org/licenses/eclipse-1.0.php">Eclipse Public License 1.0</a>, which can be found in the file
          epl-v10.html at the root of this distribution. By using this software
          in any fashion, you are agreeing to be bound by the terms of this
          license. You must not remove this notice, or any other, from this
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